Apache Kafka is an open-source communication broker written in Scala that aims to provide a united, low-latency platform, high-throughput for handling real-time data feeds. Kafka integrates with Apache Zookeeper which is a distributed configuration and harmonization service for large distributed systems. Apache Kafka is a messaging scheme for the age of big data, with a strong focus on scalability, reliability and message throughput. This is the first part of a short sequence of posts on how to secure an Apache Kafka broker. Kafka aims to provide low latency, high-throughput for real-time data feeds. It is widely used for Complex Event Processing; Log aggregation real-time streams analytics, ingestion data into Spark, etc.